Rig sqlite3_serialize() so that it will initialize a previously uninitialized

database prior to serializing it, so that it does not have a zero-byte size
and does not return NULL (except for OOM).
[forum:/forumpost/498777780e16880a|Forum thread 498777780e16880a].

FossilOrigin-Name: e638d5e408ea2e189b6771d16bbc2e42c606e88e05fbea78079b6e39e41f344c

1 files changed, 8 insertions, 0 deletions

diff --git a/src/memdb.c b/src/memdb.c
index 657cb9ca6..d83a51d54 100644
--- a/src/memdb.c
+++ b/src/memdb.c
@@ -799,6 +799,14 @@ unsigned char *sqlite3_serialize(
     pOut = 0;
   }else{
     sz = sqlite3_column_int64(pStmt, 0)*szPage;
+    if( sz==0 ){
+      sqlite3_reset(pStmt);
+      sqlite3_exec(db, "BEGIN IMMEDIATE; COMMIT;", 0, 0, 0);
+      rc = sqlite3_step(pStmt);
+      if( rc==SQLITE_ROW ){
+        sz = sqlite3_column_int64(pStmt, 0)*szPage;
+      }
+    }
     if( piSize ) *piSize = sz;
     if( mFlags & SQLITE_SERIALIZE_NOCOPY ){
       pOut = 0;